As a substrate processing apparatus, there is known an apparatus which coats a chemical solution dispensed through a nozzle onto a substrate. While dispensing the chemical solution through the nozzle is stopped, solidified objects of components contained in the chemical solution may occur in the nozzle because the solvent contained in the chemical solution remaining in the nozzle evaporates. If these solidified objects are dispensed onto a substrate, a chemical-solution coating failure or defects in the processed substrate occur, resulting in a decrease in the productivity of the substrate processing apparatus. If the chemical solution is periodically dispensed through the nozzle in order to prevent solidified objects from occurring, the amount of the discarded chemical solution increases.